Adding product to cart issues

Hello, i want to add a product to cart when clicking on the #tool-buy button but its not working and its seems like i dont even have the cart.js and the cart/add.js files

What error do you get?

Those endpoints are provided by Shopify so you don’t need files for them.

got a 404 error :

{"status":"bad_request","message":"Parameter Missing or Invalid","description":"Required parameter missing or invalid: items"}

https://get-quark.com/en/pages/le-configurateur-quark the web page link